[llvm] [mlir][bufferization] Don't clone on unknown ownership and verify function boundary ABI (PR #66626)

[Matthias Springer via llvm-commits]

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@@ -132,30 +132,79 @@ void DeallocationState::getLiveMemrefsIn(Block *block,
   memrefs.append(liveMemrefs);
 }
 
-std::pair<Value, Value>
-DeallocationState::getMemrefWithUniqueOwnership(OpBuilder &builder,
-                                                Value memref, Block *block) {
-  auto iter = ownershipMap.find({memref, block});
-  assert(iter != ownershipMap.end() &&
-         "Value must already have been registered in the ownership map");
-
-  Ownership ownership = iter->second;
-  if (ownership.isUnique())
-    return {memref, ownership.getIndicator()};
-
-  // Instead of inserting a clone operation we could also insert a dealloc
-  // operation earlier in the block and use the updated ownerships returned by
-  // the op for the retained values. Alternatively, we could insert code to
-  // check aliasing at runtime and use this information to combine two unique
-  // ownerships more intelligently to not end up with an 'Unknown' ownership in
-  // the first place.
-  auto cloneOp =
-      builder.create<bufferization::CloneOp>(memref.getLoc(), memref);
-  Value condition = buildBoolValue(builder, memref.getLoc(), true);
-  Value newMemref = cloneOp.getResult();
-  updateOwnership(newMemref, condition);
-  memrefsToDeallocatePerBlock[newMemref.getParentBlock()].push_back(newMemref);
-  return {newMemref, condition};
+Value DeallocationState::getMemrefWithUniqueOwnership(
+    const DeallocationOptions &options, OpBuilder &builder, Value memref,
+    Block *block) {
+  // NOTE: * if none of the operands have the same allocated pointer, a new
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matthias-springer wrote:

operands of which op? what does `same` refer to?

https://github.com/llvm/llvm-project/pull/66626